## How Not to Infer an Inference

The last time we talked about reading comprehension, we focused on questions that are really asking why, as opposed to asking what. Another type of question word that we need to make sure we understand correctly is the word inferred. Inferred, along with its tricky friends suggested and implied, tends to make our minds wander away from the information in the passage on the computer screen and out to somewhere in the real world. And that’s why we get these questions wrong. The key to doing well on questions of the infer, imply, and suggest variety is remembering that the correct answer will always be supported by the text. Let’s look at the passage on page 392 of the Official Guide (13th Edition) as an example.

Questions 65, 67, and 68 all use the word inferred. We need to find out what the passage says explicitly about the subject of each of these questions and then find answer that matches.

A)     Lighter isotopes of oxygen

B)      More gaps in its sequence

C)      Climate shifts

D)     Compares ocean water to fresh water.

E)      Only a million years old

Answer B is the only match. The cited benefit is a continuous record, so gaps would make it less beneficial. Even the official explanation quotes this line. In fact, if you look at the explanations to all of these questions in the answer section of the Official Guide, you will notice that each answer says that “Any inference…needs to be based on what the passage says.” Keep that in mind. An inference in real life is not the same as a GMAT inference. Always looks for the answer that is stated directly. Let try two more.

Question 67 focuses on precipitation from evaporated ocean water. The answer is clearly stated in lines 20 through 23. These lines say that heavier isotopes are left behind during evaporation, so the non-evaporated water has a lot of oxygen 18. This is means that the evaporated water that becomes precipitation must have less oxygen 18 since it was left behind. This is exactly what answer B says. Answers C (continental ice sheets), D (water on land), and E (oxygen 16) all have the wrong focus. Answer A can be eliminated just by reading carefully.

Question 68 focuses on calcium carbonate shells, which are discussed in lines 24 through 29. According to that part of the paragraph, the shells contain oxygen atoms from the surrounding ocean water. Reading backwards through that sentence, we learn that the enrichment levels (of oxygen, as stated in the preceding sentence) can be determined from analyzing the sediment created by those shells. If you haven’t already learned from answering previous questions that the oxygen enrichment referred to and the isotope record are the same thing, you may have to read further back in the paragraph. But if you do already know that, then the answer is definitely E. Again, the other answers focus on subjects that are not relevant to the question. A focuses on deterioration, B on a comparison to ice age sediment, C on ice, and D on radioactive material. None of those were discussed in the lines that talk about calcium carbonate shells, but we do have clearly stated proof in the passage for answer E.

Notice how we did not read the whole passage ahead of time to answer these questions. Instead, we skimmed the passage looking for key words from the question. This can be a useful strategy for saving time. Of course, if you have a primary purpose or main idea question first this may not work as well, but inference questions do not require knowledge beyond the immediate subject of the question.

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## What is Your Dream GMAT Score?

One question that a lot of people have is just what exactly their GMAT score means. They aren’t sure what a “good” score is and how much improvement they can reasonably expect to see after investing time in studying for the test. They may not be certain whether they should apply for programs that have a mean or median score that is higher than what they achieved on their test. Today’s post will break down the four main sections to help you understand these issues better.

Analytical Writing

The mean score for Analytical Writing is 4.4, out of a total possible score of 6. This score is not incorporated into the composite score. The Guidelines for Using GMAT Scores strongly discourage decision making about applicants based on a one-point different on the Analytical Writing Score. The Guidelines also recommend carefully considering that impact of a non-native English speaker’s deficiency in English on his overall test score and to not necessarily see low scores in those cases as an indicator of poor reasoning skills.

Integrated Reasoning

The mean score for Integrated Reasoning is 4.33, out of a total possible score of 8. This score is not incorporated into the composite score. As this section is very new, schools are not reporting the mean or median Integrated Reasoning scores of accepted applicants.

Verbal

The mean score for Verbal is 27.6, out of a total possible score of 60. This total is a bit deceptive though. A score of 9 will place you above just 1% of all test takers, and a score of 45 will place you above 99% of all test takers. So even though the average might be 27.6 and the top score 60, a 42 is an incredible score that puts you in the 96% ranking. In addition, the percentage gains are not constant. For example, 31 to 32 raw score is a 5% increase, 32 to 33 raw score is a 3% increase, 33 to 34 raw score is a 2% increase, and 34 to 35 raw score is a 5% increase. Don’t assume that all 5 point increases have the same impact on your total score or your percent ranking.

Quantitative

The mean score for Quantitative is 37, also out of a total possible score of 60. Note how much higher the quantitative mean is than the verbal mean. Keep that in mind when you are comparing your raw scores to decide on which section to focus your studies. The total is again deceptive. A score of 7 will place you above just 1% of all test takers, and a score of 51 will place you above 99% of all test takers. However, just one point lower, a 50, drops you to the 90th percent ranking and two points lower, a 49, drops you all the way to the 83% ranking. Keep this important difference between the quantitative and verbal sections in mind when you decide whether to take the GMAT a second or third time. If your raw quantitative score is near the top of the scale, getting just a one point raw score increase could be a big deal for your composite score.

Composite

For the composite score, which is made up only of the Verbal and Quantitative Sections, a 544 is the mean score. A 760 will put you at the 99% ranking and a 500 drops you all the way to the 33% ranking. The minimum score is a 200. Because of these variations, it is difficult to predict how many points you can increase with a certain amount of studying. Going from a 400 to a 500 is a 21% increase, which is easier than going from a 500 to a 600, a 29% increase. In general, the lower your score is to begin with, the easier gains are to achieve.

Also remember that the Guidelines for Using GMAT Scores state that there is a standard error of measure of 29 points. This means that if you took the GMAT three months in row without studying in between attempts, you could expect to see a difference of 30 points higher or lower than your original score on each subsequent test. However, because any test, no matter how well designed, can only be an estimate of your abilities, GMAC goes beyond that 29 point error and recommends using a 40 point standard error of difference for decision purposes. What does that mean for you? It means that all else (GPA, work experience, interview, recommendations, etc) being equal, if you got a 600 on the GMAT and another candidate got a 640, your scores should be viewed as equal. It also means that schools are strongly discouraged from having a hard cut-off point for GMAT scores. It wouldn’t make sense to toss an application with a 590 GMAT automatically, when a 590 could be the same as a 610. So don’t discourage yourself from applying for a school that you may think is a little out of your reach based on reported scores of accepted applicants. Be sure to consider all factors that you bring to the application package.

Want more information on how your GMAT score will be interpreted and used by schools? There is no better place to get it then from the folks at GMAC themselves!

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## Just What is the Role of Those Sentences Anyways?

If you have already been practicing Critical Reasoning questions on the GMAT, you have likely worked a lot on assumption, strengthen, weaken, and inference questions. While those are the question types that you are likely to encounter with the most frequency on the GMAT, there are other minor types too. One of those is the boldfaced sentence type. These arguments have two sentences printed in bold type and it is your job to correctly identify the role of those sentences. These questions are asking about the structure, rather than the topic, of the argument. Although the task you must complete is different, the skills you need for this question type are the same as those for the more common question types. The sentences will be premises or conclusions, so you have to be able to identify those. Let’s review.

A premise is a fact, a statement that is indisputable. It comes from observation, research, a publication, or some other location of public record that could be used to verify the information. While you may not believe some of the premises given on the GMAT, you have to accept them as true since you don’t have access to resources for fact-checking.

A conclusion is what the author is trying to convince you of. Often times, conclusions can be identified through key words such as conclusion, clearly, suggests, hypothesizes, and therefore. Other times, they are a bit trickier. Just remember that they are statements that cannot yet be proven as fact. Any type of recommendation, plan, opinion, or future statement cannot be proven, so those types of statements are also conclusions.

If you can identify premises and conclusions, you can quickly eliminate answer choices on the boldfaced sentence critical reasoning questions. Let’s look at #78 on page 524 of the Official Guide (13th Edition) as an example.The first boldfaced sentence is a premise. You could look up insurance records in various countries to find the evidence. The second boldfaced sentence is a conclusion because the sentence begins with clearly, which, of course, is not boldfaced. Be sure to read the whole sentence when working on these questions. Let’s see how quickly we can eliminate answers with what we have just figured out.

A)     A claim is a conclusion. Eliminate this answer based on boldfaced sentence 1.

B)      A claim is a conclusion. Eliminate this answer based on boldfaced sentence 1.

C)      Finding and conclusion are consistent with our analysis. Keep this answer for now.

D)     Finding and claim are consistent with our analysis. Keep this answer for now.

E)      Evidence is a premise. Eliminate this answer based on boldfaced sentence 2.

What is nice about having two part answers like these is that we don’t always need to use the entire argument to eliminate wrong choices. An answer that is half wrong is completely wrong. Sometimes, you can even find the correct answer by just using one sentence, although not in this case.

Now, let’s look back at the remaining choices. The full content of those answer choices cannot be properly analyzed without looking at the whole argument. Remember, this is a structure question, so let’s not worry about the topic; we’ll look at the structure instead.

Sentence 1: A premise

Sentence 2: A premise that describes a problem with analyzing the first premise.

Sentence 3: An inappropriate conclusion that some might draw from the premises.

Sentence 4: A valid conclusion.

We can see that there are two conclusions here, so we should keep that in mind when we dig deeper into our remaining answer choices.

C)      The first part of this answer claims that the second premise supports the first conclusion. This is clearly not true based on the analysis above.

D)     This answer is correct. In the first part of the answer, implications are the same as a conclusion and the first conclusion is at issue. The second part of the answer is true because the second conclusion argues against the first.

As you can see, you probably will have to read the entire argument, not just the boldfaced sentences, to arrive at the correct answer. But don’t do so unless you have to. Save yourself the time if you can by eliminating answers based just on whether they are premises or conclusions.

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## 5 Good Reasons to Throw Away Your Calculator

Like most students, you may find it incredibly unfair that you aren’t allowed to use a calculator on the main quantitative portion of the GMAT. Even though all test takers are in the same boat, which means the impact on your score percentile is non-existent, it can still be incredibly frustrating to suddenly have to use a marker and white board, or just your brain cells, to do calculations that you have been doing in a spreadsheet or with a calculator for over a decade. However, the GMAT is intended to be a reasoning test, not a quantitative achievement test. If you are working out extensive calculations on your white board, you aren’t approaching many the problems correctly. Working on mental math skills (such as estimation, identifying patterns, and using properties of numbers) will certainly boost your GMAT score, and, believe it or not, there are several real world benefits that come from improving your mental math skills as you practice for the GMAT. These include:

1)      Restaurant Etiquette – Don’t try to deny it. We have all been in a situation at least once with a group of people in a restaurant after the bill has come and no one can figure out his fair share accurately, and, heaven forbid, figure out the tip on top of that. While such a situation may only be mildly annoying among friends, not being able to quickly and accurately calculate a tip while at a business lunch could be downright embarrassing.

2)      Getting the Right Change – Cashiers sometimes make mistakes. If you know how much change to expect, you can ensure that the mistake doesn’t end up coming out of your wallet. And conversely, you wouldn’t want to call out a cashier for giving you the wrong change when in fact she was right all along. That could also be quite embarrassing.

3)      Recognizing a Bargain – OK, maybe you never pay in cash, so the second benefit of mental math doesn’t apply to you. But everyone loves a bargain. Prices in stores can be intentionally deceptive, and what looks like a good deal may not be at all. If single cans of dog food are on sale for \$1.30 each (marked down from their usual \$1.70), that seems like a great deal. But the twelve-pack (inconveniently placed on a lower shelf) is only \$14. You may be drawn to the sale price, but the regularly priced twelve-pack is still cheaper. Now, \$1.60 may not seem like a big difference, but you can bet that bit of advertising trickery happens with big ticket items as well. If you have to punch the numbers into your cell phone’s calculator (And what if you forgot your cell phone at home?) for twenty or thirty items on your shopping list, you could really extend the length of your trip. Mental math can be a time saver.  Want a quick tip for this mental math example? You already know that \$1 times 12 is \$12, so just multiply 3 by 12, to get 36. Add on the zero, remember the decimal places, and you should get a quick total of \$15.60 in your head for the twelve individual cans.

4)      Staying Healthy – Many studies have supported the connection between staying mentally active and having good mental health well into old age. Not relying on your calculator as often just might help you stave off the cognitive decline associated with diseases such as Alzheimer’s.

5)      Impress Your Friends – Looking at a number such as 426,212,088 for just 3 seconds and being able to tell your friends that you know it’s evenly divisible by 12 may not be a useful skill, but it’s a fun party trick. How can you do that? Well, when the last 2 digits of any number make a number divisible by 4, then the whole number is divisible by 4 (88/4). And when all the digits of a number add up to a number divisible by 3, then the number is divisible by 3 (4+2+6+2+1+2+0+8+8 = 33). And any number that is divisible by both 3 and 4, must be divisible by 12. You can perform this fun party trick and many more, all thanks to mental math.

Why not take your GMAT study as an opportunity to really flex your mental math muscle?

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## Do You Ever Stop to Wonder Why?

Reading comprehension is often a test-taker’s least favorite part of the GMAT. The passages are dense and boring, and reading on a computer screen can be uncomfortable. These factors make it tempting to gloss over passages. And this may be just fine, because different people have different reading styles. But regardless of whether you are someone who prefers to read the passage thoroughly or to just jump straight to the questions, you need to understand the questions properly in order to avoid trap answers. Let look at question 102 on page 405.

The question uses the words “in order to.” What does that really mean? Phrases such as in order to, the role of, serves to, and the purpose of are all asking why a particular detail has been included in the paragraph. Why does an author include any detail in his writing? To support the point he is trying to make. So any question that is asking why on the GMAT is really about the main idea of the paragraph. And where can the main idea of a paragraph typically be found? In the first or last sentence. Since the detail sentence the question refers to is the last sentence, we should look at the first sentence. This sentence indicates that researchers should obtain a more representative sample of the total population with the disease. Every other sentence in the paragraph is there in order to explain why this is a good idea. Let’s look at the answers.

A)     Even if you haven’t read the passage, remember that extreme answers are almost never correct on the GMAT. It is difficult to state that a variable is the most critical if only certain variables are discussed in this brief passage.

B)      This answer is the opposite of what the paragraph attempts to accomplish. The paragraph supports Frazier and Mosteller; it doesn’t cast doubt on them. Opposite answers can be attractive because they have all the right words about the topic.

C)      This answer refers to the sentence right before the sentence the question is asking about. That sentence (lines 30 – 33) begins with for example, so it is also a supporting detail, not the main idea.

D)     Yes, a wide range of patients is a good paraphrase of the main idea which was about a more representative sample.

E)      This answer also goes against the main idea of the paragraph, rather than supporting it.

It is not necessary to read the whole passage to be able to answer a why question. Just find the main idea of the paragraph that contains the sentence referred to in the question, and then select the answer that refers to the main idea.

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## GMAT Skills in Real Life: Topic 2

Finally – a store that got it right! Despite a very simple rule that less is used for what cannot be counted (snow, anxiety, interest, beer) and fewer is used for what can be counted (snowflakes, moments of anxiety, interesting people, bottles of beer), grocery stores across America stubbornly refuse to change their “10 items or less” signs. This may lead one to believe that proper grammar and diction don’t matter, but they do.

A spate of recent articles suggests that proper grammar in the workplace may be more important than you realize. The Wall Street Journal story This Embarrasses You and I* kicked off a series of related articles this summer that all emphasized the importance of grammar during a job hunt and in the workplace. (See also Why Grammar Counts at Work and I Won’t Hire People Who Use Poor Grammar. Here’s Why.) Bad grammar is all around us and some people—people who may matter a lot to your career—really do notice it.

Sticklers for grammar might find those who are truly ignorant of the rules obnoxious, but they might also find the over-correctors just as bad. The over-correctors are those people who think that whichever word sounds more formal or educated is the grammatically correct one, and then they sneer at the people who actually follow the rules, regardless of sound. The most egregious of such violations include saying I instead of me, well instead of good, and whom instead of who. Here is a quick refresher:

I: the subject (person doing the action) of a sentence or phrase

She said that I was the person in the Darth Vader costume at the Halloween party.

Mitchell and I studied together for the GMAT, but I scored much higher than he did.

Me: the object (person receiving the action) of a sentence or phrase

The professor was smiling as he handed the midterm back to Graham and me.

Just between you and me, I think my sister’s new restaurant serves terrible food.

How are you doing? I am doing well.

Good: an adjective. Commonly answers the question “what is it like” in order to describe a noun.

How are you? I am good.

*If you aren’t sure whether you should say well or good, simply substitute in another adverb or adjective. You would never say I am quickly or I am happily, so you shouldn’t say I am well. The construction I am needs to be followed by an adjective.

Whom: the object (person receiving the action) of a sentence or phrase

Whom did you call to ask about the city’s policies on leaf collection?

The person next to whom you were seated was wearing an enormous sunhat.

Who: the subject (person doing the action) of a sentence or phrase

Who called us to ask why we hadn’t put our leaves into clear trash bags?

The person who was wearing the enormous sunhat was seated next to you.

*Again, a simple substitution can clear up any ambiguity. If you think you should use whom, try substituting another object pronoun (him, them, her, us).  If you think you should use who, try substituting another subject pronoun (he, they, she, we).

Even if you are an accountant or a programmer, Kyle Wiens won’t hire you if you can’t pass his grammar test, and you can bet that other employers feel the same. So while you may not see any practical use of the Pythagorean Theorem or the ability to logically complete an argument beyond the GMAT, consider the time you spend practicing for the Sentence Correction portion as a little investment in your future. Proper grammar just might give you an edge over the competition when you get out there in the real world.

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## GMAT Skills in Real Life: Topic 1

Supposedly more than a test of basic math and grammar skills, the GMAT claims to accurately assess your ability to:

–          interpret graphic data

–          reason quantitatively

–          recognize which information is relevant

–          reason and evaluate arguments

–          analyze information from a variety of sources

–          develop strategies and make decisions

Clearly, these are all skills that are useful in business school and corporate America, but most GMAT test-takers still wonder about the connection between the test and reality. They view it as an unfair and pointless barrier blocking the way to the next phase of their lives. And they certainly don’t take their studies and test results as an indication of their business acumen. Nor should they!

Nonetheless, it can be interesting to think about how GMAT questions might reflect real life concerns. Take percent change for example. A common GMAT trap on both quantitative questions and critical reasoning is to present information in percentages and draw a conclusion based on concrete numbers.  Doing so can be misleading.

Say that the price of a stock decreases 50 percent over the last year and then rebounds 80 percent this year. You may think you’ve earned money on your investment. However, if you invested \$1,000 dollars and the price decreased to \$500, 80 percent of \$500 is \$400, so you now have only \$900. You lost money.

Likewise, if your \$1,000 investment increases by 200 percent, you now have \$3,000 but if it then decreases by 50 percent, you drop all the way back down to \$1,500, not to \$2,500 (sell while it’s hot!). If you’ve read the chapter of my book on assigning values, you might understand better now why it can be important to do so. Percent change can be very deceptive.

As a side note, don’t forget that 200 percent of and 200 percent more than are calculated differently. While of signifies multiplication, more than signifies addition. So 1,000 is 200 percent of 500 and 1,500 is 200 percent more than 500. That’s quite a discrepancy if you are negotiating the salary increase you hope to obtain once you finish your MBA studies!

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## Working with Factors and Divisibility

One of the many GMAT math concepts that we learn in grammar school but probably don’t use very often in real life is how to work with factors. Factors are numbers that go into other numbers evenly. For example, 3 and 4 are factors of 12. Prime factors (numbers divisible only by one and themselves) help us realize whether one very large number is divisible by another.

For example, the prime factors of 108 are 2, 2, 3, 3, and 3 and the prime factors of 36 are 2, 2, 3 and 3. If we write those out as a fraction, we get:

2 × 2 × 3 × 3 × 3
2 × 2 × 3 × 3

Every prime number in the denominator can be cancelled out by a prime number in the numerator, so 36 is a factor of 108. The numerator can have a lot of different prime factors left over. All that matters is that the prime factors in the denominator are cancelled out. Here’s another example with  18036:

2 × 2 × 3 × 3 × 5
2 × 2 × 3 × 3

The 5 in the numerator doesn’t correspond to any numbers in the denominator, but that doesn’t matter. Every prime factor in the denominator can be cancelled out. For a counter example, let’s try 27036:

2 × 3 × 3 × 3 × 5
2 × 2 × 3 × 3

There are two 2s in the denominator, but only one 2 in the numerator, so we are unable to cancel out all prime factors in the denominator, and we then know that 270 is not evenly divisible by 36.

So how can we use this concept on the GMAT? Let’s look at question 116 on page 168 in the GMAT Official Guide, 13th Edition. P, the numerator, will include every prime factor for every number 1 through 30 inclusive. However, the only prime number in the denominator is 3. So the question is really asking how many 3s there are in the numerator. However many 3s are in the numerator will be the same amount that can be in the denominator and be cancelled out to make 3k a factor of P. Take every number in the range that is a multiple of 3 (3, 6, 8, 12, 15, 18, 21, 24, 27, and 30) and count up the 3s. Remember that some may have more than 1 (for example, 27 = 3 × 3 × 3). The total is 14, answer C.

Let’s also have a look at question 77 on page 163. When we work with factors and multiplication, the prime factors in the denominator only have to be cancelled out by one prime factor in the numerator. But addition and subtraction are a bit more complicated in that every number in the numerator needs to have the same prime factors as the ones you want to cancel out in the denominator. Here is an example with (72 + 24)12:

(2 × 2 × 2 × 3 × 3) + (2 × 2 × 2 × 3)
2 × 2 × 3

The 2, 2, and 3 in the denominator exist in both the prime factors of 72 and 24.

(2 × 2 × 2 × 3 × 3) + (2 × 2 × 2 × 3)
2 × 2 × 3

So 12 is a factor of 72 + 24. However, if we try (46 + 24)12 we get

(2 × 23) + (2 × 2 × 3 × 3)
2 × 3 × 3

We don’t have the right prime factors in 46 to be able to cancel out those in the denominator, so 12 is not a factor of 46 + 24. Since question 77 has addition, we know that the correct answer must have the same prime factors as both 20! and 17. Since 17 is a prime number, it is only divisible by 1 and 17, so 15 and 19 cannot be factors of the expression.

Factors can be more complicated than just a single number. So stay tuned and in a few weeks we’ll discuss a few more problem solving questions that use factors.

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## You Bought the Books, Now What?

1)      Skipping over the basics. Some people want to dive right into realistic GMAT questions, and for some people, that’s fine. Others, however, can’t remember how to add fractions or what the formula is for the area of a triangle. If you are struggling with the basic concepts – brush up on them first. The GMAT Official Guide has lots of basic math information before the problem solving section. Make flashcards for formulas and properties of numbers that you don’t remember. You can’t expect to solve the 37 quantitative questions in the time allotted if you are struggling with the concepts. You also can’t focus on good test taking strategies, like backsolving and estimation, if you can’t grasp what the question is asking.

2)      Avoiding topics they think they know well. If you think back to middle school and remember that you were an algebra-whiz kid, you might think you should focus on statistics and sentence correction. However, middle school was a long time ago and solving algebra questions on the GMAT is a whole different experience. It’s just as important that you practice the topics you think you are good at as those you have a hard time with. Keep in mind that the test is computer adaptive. If you get the easy and medium algebra questions correct right away, the test is going to give you some real whoppers.

3)      Avoiding topics they don’t like. On the flip side, don’t avoid the topics you know you have a hard time with (ahem…reading comprehension!). Don’t make the mistake of thinking that reading comprehension is only about a third of the verbal, and that if you ace sentence correction and critical reasoning, you’ll get a great score. Chances are that you will make at least a few mistakes in sentence correction and critical reasoning, so you can’t rely on those topics only for a high verbal score. If you spend a bit of time with those boring reading comprehension passages (or whatever your nemesis is), you might find that you can get a few extra points more easily than you think.

4)      Thinking more and more and more practice is the best approach. The study schedule that my book lays out includes a lot of time spent reviewing questions that you miss in your practice. Looking at the right answer and moving on immediately doesn’t help. Reviewing questions you missed means checking to see whether you made simple calculation errors, checking to see whether you missed an opportunity to use a strategy, and noting patterns in the types of questions you miss so you know what to focus your study efforts on. Use the “standardized” part of this standardized test to your advantage. Questions are about concepts and patterns, not individual questions. If you take the GMAT 20 times, you will see roughly the same 37 quantitative questions each time, just with different words and numbers. You don’t need to see an example of every type of question that has ever been on the GMAT. You just need to recognize the concept that is tested in each question and have an approach for that concept. Reviewing missed questions helps you figure those concepts out.

Image Courtesy of Joe Lanman with Creative Commons License

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## How to Match the Answers to the Text in Reading Comp

As you are probably used to hearing me say by now, every reading comprehension answer has to be clearly supported by information in the text. Even when a question is written as a hypothetical scenario, there will be evidence in the passage that supports the correct answer. However, it can be easy to let your mind wander outside of the information in the passage when a question is hypothetical. In today’s post, we’ll practice with two such questions so that we can master good techniques.

The first is question 112 on page 408 of the GMAT Official Guide, 13th Edition. The first step to answering this question correctly is taking the time to articulate the method that the author finds problematic. This is found in lines 7 – 9, which say that we shouldn’t remove a species that might be the keystone species then observe changes in the ecosystem. Now that we have identified the problem, we just have to look through the answers to find an experiment that does just that. Answer C explicitly mentions removing a species and then observing the ecosystem after that species is gone. This is correct.

While the answer to this question may have been relatively easy to identify, you can still look at the other answers to understand the ways in which the GMAT test writers attempt to trap you. Most of the wrong answers discuss topics related to keystone species that are discussed in the passage as well. Answers D and E discuss the influence of different environments on the keystone species, as is discussed in lines 118 – 122. Answer B discusses the possibility of another species occupying the keystone role, as is discussed in lines 27 – 29. On more difficult questions, if you don’t take the time to articulate the author’s position first, you could easily be attracted to one of these distractor answers.

Let’s try one that is more difficult – number 123 on page 413. Here, we need to first articulate the social constructivists’ version of technological determinism. The evidence is tricky to find because of the wording of the paragraph in which we find the answer (lines 25 – 32). You may need to read this paragraph carefully to understand that it does actually give the social constructivists’ version, not the true beliefs of the technological determinists. The constructivists’ version is that machinery imposes forms, and technology directly influences skills and work organization. Answer A is a direct match for that idea. Other answers, like B and C, support Clark, who refutes this version of technological determinism.

If you struggle with this question, remember to wary of answers that are extreme. Answer B uses the word all and answer D uses the word most. Such words are rarely supported by the passage. If you don’t see those extreme ideas expressed in the passage, they aren’t correct.

Image Courtesy of Horia Varlan with Creative Commons License